This invention relates, in general, to connectors for coaxial cables of the type used for radio frequencies (RF), such as those carrying signals with high frequency and low power associated with cellular telephone base stations. In one aspect, the invention relates to an elbow connector between a length of such cable and a piece of equipment, such as a base station radio. Such connectors are referred to as Sub Miniature A interface (SMA) connectors. Typically, they have been complex structures, which require extensive assembly time. Consequently, simpler, more easily fabricated connectors have been sought by the industry to facilitate installation of cables to equipment.
When a coaxial cable is to be connected to a piece of equipment through a connector, the inner contact of the connector must be securely attached to the cable in order to provide adequate transfer of the signal. In some cases, this is done by soldering the cable""s inner conductor to the inner contact of the connector, as will be seen below in the description of two commercially available connectors. Both of them require soldering during assembly. The cables and connectors are relatively small, and it would be preferable to avoid soldering of the cable to the connector during installation.
In other connectors, the inner contact is not soldered, but is retained within the body of the connector by insulating sleeves inserted into each end which do not completely fill the space between the inner contact and the body. The present inventors have found a method of making a connector which avoids the soldering of the inner conductor of the cable to the inner contact of the connector and also simplifies making the connectors and assembling coaxial cables to radio equipment. This connector, as described in detail below, is less expensive to produce and easier to use in connecting coaxial cables to RF equipment.
In one aspect, the invention has the object of providing an improved lower cost connector for joining a coaxial cable to an RF component. A conductive metal body has a unitary inner contact positioned within a channel in the body and retained there by an electrically insulating material injected into the channel.
Another object of the invention is to provide a connector which does not require soldering of the inner contact during assembly to an RF component, as was typical of prior art connectors.
It is also an object of the invention to provide a conductor in which only the conductive metal sleeve used to connect one end of the metal body is soldered to the outer conductive jacket of the cable, while a conductive metal nut mounted on the other end of the metal body is used to connect the cable to the RF component, e.g., a base station radio.
A further object of the invention is to provide a method for making a connector for coaxial cables which is ready for assembly and does not require soldering of the inner contact.